Modern wireless and wireline data communications networks employ packet data processing and exchanges at various layers within digital data communication's Open System Interconnection Reference Model (the OSI model). As would be understood by those skilled in the art, the OSI Model is an abstraction that defines conceptual, layered communications and computer network protocol design. At its core, the OSI model divides a network's communication architecture into seven distinct components, which include the following layers (from top to bottom): Application, Presentation, Session, Transport, Network, Data-Link, and Physical Layers. Generally, a particular OSI layer provides services to the layer above it and additionally the same OSI layer also receives services from the layer below it. Depending on where a given layer resides within an OSI stack, there may or may not be a layer above or below it with which the layer exchanges services.
In the context of a layered protocol stack, a unit of data specified in a given layer is commonly referred to as a protocol data unit (PDU). The PDU typically includes both payload and overhead (i.e., header information) data. A PDU may be referred to by other terms, such as a frame, a packet, a segment, a message, and so on . . . . In order to facilitate network communications, layered protocol stacks must facilitate transfer of PDU data amongst different portions (e.g., both wireless and wireline portions) of a data communications network. At each protocol layer, header information exists that can comprise a variety of data transfer information. Header data size generally remains constant for a given protocol layer, but it can also be variable. As data is passed to lower layers of the protocol stack, additional header information, specific to that layer can be added to the PDU. As data is passed to upper layers of the protocol stack, header information that is not used by the upper layers is generally removed from the PDU.
A PDU header may contain crucial data transfer information as well as instructions about data being carried in a particular PDU's payload. This information and these instructions may include, but are not limited to: a destination address (e.g., an IP address where a PDU is being routed through or delivered to), an originating address (e.g., an IP address where a PDU came from), PDU size information, synchronization information that allows a PDU to be compatible within an existing network infrastructure, a PDU sequence number that identifies which PDU a current PDU pertains to in a sequence of PDUs, a PDU protocol (with networks that carry many different types of information, the PDU protocol may define what type of PDU is being transmitted: e-mail data, webpage data, streaming video data, image data, etc.), encryption security data (encapsulating security payload information), etc.
Each PDU payload of a particular data transmission typically has a fixed-size PDU header attached to it before it is sent over a network communications link in a distributed data communications network. The PDU header is subsequently removed from the PDU payload at the receiving end of the network communications link so that sequenced payload data can be reassembled at a receiving device. In general, a PDU header represents a fixed communication link overhead that is required to ensure that PDU payload data is correctly routed to its delivery destination.
As would be understood by those skilled in the Art, with a constant PDU payload throughput (e.g., a throughput measured in Mbps) on a particular network communications link, the total PDU throughput (including fixed-size PDU header data, measured in bytes) depends on an average PDU payload size. By way of example, if an average PDU payload size decreases on a network communications link, while the PDU payload throughput remains constant, then an actual link throughput will increase in proportion to the decrease in the average PDU size. Likewise, if an average PDU payload size increases on a network communications link, while PDU payload throughput remains constant, then an actual link throughput will decrease in proportion to the increase in the average PDU size. Due to the fact that an actual link throughput can drastically change with respect to variations in average PDU payload size (as the average PDU payload size decreases, while PDU payload throughput and header data size remain constant), there can be extreme scenarios where actual link throughput may be negatively impacted based on the nature of data communications that result in a relatively small average PDU payload data size (e.g., if the average PDU payload size is less than a designated multiple of the PDU header size, such as ten times the PDU header size).
Modern service providers commonly employ rate-limiting schemes that limit the PDU payload throughput in vacuum of the various data types that are being transferred across network communications links within portions of a larger data communications network. Further, present day service level agreements may not account for total PDU throughput, based on both payload and header size information, when allocating network resource limits to subscribers via various predetermined data-rate plans.
Considering how different data types can affect the relationship of an average payload size compared with an average or constant header size can be very important for network resource planning considerations. For example, in a case where communications of a particular data type results in a small average payload size, in relation to a constant PDU header size, a total throughput consumed on a communications link is substantially larger than the throughput of the PDU payload data alone. This additional link throughput may be much larger than a service provider anticipated when they drafted their service level agreements for regional network subscribers. Accordingly, service providers should account for more than just user-generated traffic represented by PDU payload throughput.
Short-sighted network traffic planning can ultimately lead to periods of network congestion (data transfer loads that burden network capacity and throughput) between links in a larger data communications network. These overload periods can degrade a service provider network's Quality of Service (QOS) as well as network service subscribers' collective Quality of Experience (QOE) within a particular network, especially during peak data transfer periods. Some negative effects of poor traffic planning can lead to adversely affected network QOS and QOE metrics, which may result in: queuing delay, data loss, as well as blocking of new and existing network connections for certain network subscribers.
It would be beneficial to have improved systems and methods utilizing hybrid rate-limiting schemes that allow service providers to advantageously plan for both user-generated traffic and for traffic generated by a user in combination with necessary traffic generated by appending PDU header data to PDU payload data. By contemplating and accounting for total PDU throughput, service providers could mitigate situations where small average payload size data would unnecessarily burden actual link throughput on a communications link within a portion of a larger data communications network. It would further be desirable to improve network resource allocation by practically enforcing hybrid rate-limiting schemes and by contractually enforcing more robust service level agreements that could affect network bandwidth maximization for a wide range of network subscribers transferring a variety different data types across portions of a distributed data communications network.